1. Field of the Invention
The present invention generally relates to a light source module and a display device, and more particularly, to a backlight module and a display device using the same.
2. Description of Related Art
Along with the development of electronic technology, flat panel display has gradually replaced the conventional cathode ray tube (CRT) display as the mainstream display. Among all the existing flat panel displays, liquid crystal display (LCD) has the most mature technique and is most broadly used. Because the panel of a LCD does not emit light itself, a backlight module has to be provided as a display light source of the panel.
Among all the light sources that can be adopted in a backlight module, the light emitting diode (LED) is one of the most adaptable one for it offers high brightness, low power consumption, long lifespan, and minor heat generation, etc. Taking the light source of a direct type backlight module composed of LEDs as an example, the LEDs are welded on a circuit board as an array through the surface mount technology (SMT), and the circuit board is disposed on a frame of the backlight module.
Each LED has different brightness even supplied with the same current. Thus, in order to increase the luminous uniformity of the backlight module, the LEDs are usually ranked based on their brightness before they are welded onto the circuit board, and those too dark or too bright LEDs are eliminated. However, the cost of the backlight module may be increased by purchasing a large number of LEDs having similar brightness. Thereby, how to apply LEDs having different brightness into the same backlight module has become an important subject in the industry.